Power line inspection vehicle

ABSTRACT

An exemplary unmanned aerial vehicle (UAV) mountable to a conductor of an aerial power transmission line system includes a body having a rotor system, a motivation system attached to the body to motivate the UAV along the conductor, a battery carried by the body and electrically connected to at least one of the rotor system and the motivation system, a monitoring tool mounted with the body and an inductive coil carried by the body and in electric connection with the battery, wherein the inductive coil is configured to harvest electricity from the aerial power transmission line system and charge the battery.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.16/778,269, filed Jan. 31, 2020, the contents of which are incorporatedby reference in their entirety herein for all purposes.

TECHNICAL FIELD

This disclosure relates in general to the field of aircraft, and moreparticularly, to unmanned aerial vehicles for inspecting aerial powerline components.

BACKGROUND

This section provides background information to facilitate a betterunderstanding of the various aspects of the disclosure. It should beunderstood that the statements in this section of this document are tobe read in this light, and not as admissions of prior art.

Maintenance of the electric power grid system requires constantinspection. Traditionally this inspection is performed by linemenphysically traversing the power lines, access from helicopters, and useof small drones. Human inspection is dangerous, expensive, and oftenrequires that the power lines be deactivated. Drones have limited flighttimes and require a human operator to be within line-of-sight, reducingthe applicability of drones for power line inspections.

SUMMARY

An exemplary unmanned aerial vehicle (UAV) mountable to a conductor ofan aerial power transmission line system includes a body having a rotorsystem, a motivation system attached to the body to motivate the UAValong the conductor, a battery carried by the body and electricallyconnected to at least one of the rotor system and the motivation system,a monitoring tool mounted with the body and an inductive coil carried bythe body and in electric connection with the battery, wherein theinductive coil is configured to harvest electricity from the aerialpower transmission line system and charge the battery.

An exemplary method of inspecting an aerial power transmission lineincludes flying an unmanned aerial vehicle to a conductor of the aerialpower transmission line system, the UAV comprising a body having a rotorassembly, a set of wheels coaxially aligned, and a battery, positioningthe set of wheels on the conductor, inspecting the conductor with amonitoring tool, moving the UAV along the conductor and harvestingelectricity from the aerial power transmission line system and chargingthe battery.

This summary is provided to introduce a selection of concepts that arefurther described below in the detailed description. This summary is notintended to identify key or essential features of the claimed subjectmatter, nor is it intended to be used as an aid in limiting the scope ofclaimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure is best understood from the following detaileddescription when read with the accompanying figures. It is emphasizedthat, in accordance with standard practice in the industry, variousfeatures are not drawn to scale. In fact, the dimensions of variousfeatures may be arbitrarily increased or reduced for clarity ofdiscussion.

FIG. 1 illustrates an exemplary unmanned aerial vehicle according to oneor more aspects of the disclosure.

FIG. 2 illustrates an exemplary energy harvesting system according toone or more aspects of the disclosure.

FIGS. 3-7 illustrate an exemplary unmanned aerial vehicle traversing andinspecting an aerial power transmission line system.

DETAILED DESCRIPTION

It is to be understood that the following disclosure provides manydifferent embodiments, or examples, for implementing different featuresof various illustrative embodiments. Specific examples of components andarrangements are described below to simplify the disclosure. These are,of course, merely examples and are not intended to be limiting. Forexample, a figure may illustrate an exemplary embodiment with multiplefeatures or combinations of features that are not required in one ormore other embodiments and thus a figure may disclose one or moreembodiments that have fewer features or a different combination offeatures than the illustrated embodiment. Embodiments may include somebut not all the features illustrated in a figure and some embodimentsmay combine features illustrated in one figure with features illustratedin another figure. Therefore, combinations of features disclosed in thefollowing detailed description may not be necessary to practice theteachings in the broadest sense and are instead merely to describeparticularly representative examples. In addition, the disclosure mayrepeat reference numerals and/or letters in the various examples. Thisrepetition is for the purpose of simplicity and clarity and does notitself dictate a relationship between the various embodiments and/orconfigurations discussed.

In the specification, reference may be made to the spatial relationshipsbetween various components and to the spatial orientation of variousaspects of components as the devices are depicted in the attacheddrawings. However, as will be recognized by those skilled in the artafter a complete reading of the present application, the devices,members, apparatuses, etc. described herein may be positioned in anydesired orientation. Thus, the use of terms such as “inboard,”“outboard,” “above,” “below,” “upper,” “lower,” or other like terms todescribe a spatial relationship between various components or todescribe the spatial orientation of aspects of such components should beunderstood to describe a relative relationship between the components ora spatial orientation of aspects of such components, respectively, asthe device described herein may be oriented in any desired direction. Asused herein, the terms “connect,” “connection,” “connected,” “inconnection with,” and “connecting” may be used to mean in directconnection with or in connection with via one or more elements.Similarly, the terms “couple,” “coupling,” and “coupled” may be used tomean directly coupled or coupled via one or more elements.

With reference to the figures, FIG. 1 illustrates an exemplary unmannedaerial vehicle (UAV), generally denoted by the numeral 10, that ismountable to a conductor of an aerial power transmission line system.UAV 10 includes a body 12 having a rotor system 14, a motivation system16 attached to the body to motivate the UAV along the conductor, abattery 18 carried by the body and electrically connected to at leastone of the rotary system 14 and the motivation system 16, one or moremonitoring tools 20 mounted with the body, and an energy harvestingsystem 22 configured to harvest electricity from the aerial powertransmission line system and charge battery 18 and or to power one ormore of the UAV systems directly. UAV 10 includes avionics, such aprocessor 24, e.g. controller, in communication with the various UAVsystems and having software and instructions for operating UAV 10 inresponse to instructions from a local or remote operator and/or tooperate autonomously. UAV 10 may include navigation sensors 26, such asglobal positioning sensors and proximity sensors, in communication withprocessor 24. Processor 24 is configured to communicate with a remotesite to transmit data from the one or more monitoring tools 20 and orreceive instructions.

Rotor system 14 includes rotor assemblies 28 including motors 30 drivingrotor blades 32. Rotor assemblies 28 may be gimballed. Motors 30 areelectrically connected to battery 18 and or electricity harvestingsystem 22. Those skilled in the art with benefit of this disclosure willunderstand that battery 18 includes other electric storage devices, suchas capacitors.

Motivation system 16 is configured to physically contact the aerialconductor (transmission line) and support the weight of the UAV and insome embodiments move UAV 10 along the aerial conductor. Motivationsystem 16 includes a set 34 of wheels 36 that are coaxially aligned toengage the same conductor. In the illustrated embodiment, UAV 10 has asingle set 34 of wheels to engage and support UAV 10 on a singleconductor. The exemplary set 34 of wheels 36 has two wheels 36; however,the set of wheels may have more than two wheels. Additional co-axialwheels 36 may facilitate stability when motivation system 16 is used tomove UAV 10 across a power line component such as a splice, suspenderclamp, or cable spacer. In some embodiments, wheels 36 are electricallydriven to rotate and to move UAV 10 along a conductor. In theillustrated example, each wheel 36 includes a motor 38. Wheels 36 mayinclude V-shaped grooves 40 to engage the conductor and conductorcomponents.

Wheels 36 are connected to body 12 by arms 42. Arms 42 position wheels36 above body 12. The center of gravity 45 of UAV 10 is positioned inthe same plane as co-axial set 34 of wheels so that a single set 34 ofwheels 36 support UAV 10 from a single conductor.

UAV 10 may include one or more monitoring tools 20. In FIG. 1 , UAV 10includes a camera for a monitoring tool. The camera may be an infraredcamera. Monitoring tool 20 may be gimballed to provide visual coverageof the components to be visually inspected. For example, monitoring tool20 may be used to inspect and monitor the conductor from which the UAVis suspended, adjacent conductors, conductor components, suspensiontowers and the like. Monitoring tools 20 may include other sensors anddevices used to inspect and monitor aerial transmission line systems.

An exemplary energy harvesting system 22 is now described with referenceto FIGS. 1 and 2 . With additional reference to the other figures,energy harvesting system 22 includes a coil 44, for example open air ormagnetic core, and an AC/DC power rectifier 46. In the exemplaryembodiment of FIG. 1 , coil 44 is positioned at wheels 36 so as to be inclose proximity to the AC power transmission line 48. For example, coil44 extends between the legs 42 connecting the set of wheels to body 12.Wires 47 may extend from coil 44 through legs 42 to the AC/DC powerrectifier 46 positioned in body 12 (e.g., frame) with the battery andother avionics. When UAV 10 is proximate to an AC transmission line 48,i.e. conductor, a portion of the magnetic field 49 generated bytransmission line 48 is converted by harvesting system 22 into power.The rectified power is used by battery 18 management system to rechargethe batteries for use by UAV systems, such as rotor motors 30, wheelmotors 38, controller 24, and monitoring tools 20 and sensors 26.

A method of inspecting an aerial power transmission line system 50 isnow described with reference to FIGS. 1-7 . Aerial power transmissionline system 50 includes one or more power lines, generally referred toas conductor 48, suspended above ground 52 by suspension towers 54.Aerial power transmission line system 50 is illustrated herein as ahigh-voltage system, however, UAV 10 and the methods disclosed hereinmay be used in other systems. Aerial power transmission line system 50may include various components, generally denoted 56, that need to beinspected and the components may be an obstacle to be navigated by UAV10. A non-exclusive list of components 56 includes conductor splices,connectors, cable-spacers, dampers, suspension towers, suspensionclamps, and marker balls. As will be understood by those skilled in theart with benefit of this disclosure, UAV 10 may navigate around, over,or past these components, e.g. obstacles, by operating the wheels todrive across the component and by operation of the rotor assemblies tofly around the component or to aide in powering the UAV across thecomponent with the wheels contacting the conductor and the component. Asis well known, conductors 48 have spans that have downgrades 58 wherethe conductor is declined downward from the tower in the direction ofthe UAV travel and inclines 60 where the UAV has to travel upward on theconductor. In accordance to some embodiments, the UAV rotor assembliesmay be operated to brake and slow the descent of the UAV on downgrades58 and the UAV rotor assemblies may be operated to help the UAV climbinclines 60 while maintaining wheels 36 on the conductor.

At FIG. 3 , UAV 10 is deployed from the ground 52 and flown to andlanded on a conductor 48, shown in FIG. 4 . UAV 10 is landed bysuspending UAV 10 on conductor 48 by set 34 of wheels 36. In thisexample, UAV 10 is suspended from a single conductor 48. UAV 10 may bedeployed in direct response from an operator or UAV 10 may beself-deployed, for example, in response to instructions included in theon-board processors. In accordance to some embodiments, UAV 10 may beself-deployed and autonomous for example to continuously monitor asection of a transmission line. Monitoring tools 20 may be operated toinspect conductor 48 and components of transmission line system 50 whenUAV 10 is proximate to system 50 as well as when UAV is suspended from aconductor.

With reference to FIGS. 4 and 5 , UAV 10 is being moved along conductor48 in the direction 62. UAV 10 may be moved in the direction 62 byelectrically driving one or more of the wheels of the set of wheels.When descending downgrade 58, the rotor assemblies may be driven tobrake and slow the descent of UAV 10. In FIGS. 4 and 5 , UAV 10 passesover a component 56, such as a cable splice. In this example, UAV 10passes over component 56 while maintaining wheels 36 on conductor 48.FIG. 5 illustrates UAV 10 ascending incline 60. UAV 10 may operate therotor assemblies to provide upward lift along incline 60.

FIGS. 6 and 7 illustrates UAV 10 navigating past a component 56 byflying around the component. As UAV 10 approaches the obstacle component56, the rotor assemblies are operated to lift UAV off of the conductor48 on a first side (FIG. 6 ) of the obstacle and to fly around theobstacle component 56 and land on the conductor 48 on the second side(FIG. 7 ) of the obstacle. Monitoring tools 20, in particular a cameracan be operated to inspect the system when UAV is removed from conductor48.

Conditional language used herein, such as, among others, “can,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements and/or states. Thus, suchconditional language is not generally intended to imply that features,elements and/or states are in any way required for one or moreembodiments or that one or more embodiments necessarily include suchelements or features.

The term “substantially,” “approximately,” and “about” is defined aslargely but not necessarily wholly what is specified (and includes whatis specified; e.g., substantially 90 degrees includes 90 degrees andsubstantially parallel includes parallel), as understood by a person ofordinary skill in the art. The extent to which the description may varywill depend on how great a change can be instituted and still have aperson of ordinary skill in the art recognized the modified feature asstill having the required characteristics and capabilities of theunmodified feature. In general, but subject to the preceding, anumerical value herein that is modified by a word of approximation suchas “substantially,” “approximately,” and “about” may vary from thestated value, for example, by 0.1, 0.5, 1, 2, 3, 4, 5, 10, or 15percent.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the disclosure.Those skilled in the art should appreciate that they may readily use thedisclosure as a basis for designing or modifying other processes andstructures for carrying out the same purposes and/or achieving the sameadvantages of the embodiments introduced herein. Those skilled in theart should also realize that such equivalent constructions do not departfrom the spirit and scope of the disclosure and that they may makevarious changes, substitutions, and alterations without departing fromthe spirit and scope of the disclosure. The scope of the inventionshould be determined only by the language of the claims that follow. Theterm “comprising” within the claims is intended to mean “including atleast” such that the recited listing of elements in a claim are an opengroup. The terms “a,” “an” and other singular terms are intended toinclude the plural forms thereof unless specifically excluded.

What is claimed is:
 1. An unmanned aerial vehicle (UAV) mountable to aconductor of an aerial power transmission line system, the UAVcomprising: a body having a rotor system; a plurality of arms connectedto the body; a battery carried by the body and electrically connected tothe rotor system; a monitoring tool mounted with the body; an inductivecoil carried by the body and in electric connection with the battery;and wherein the inductive coil extends between the plurality of arms andis configured to harvest electricity from the aerial power transmissionline system and charge the battery.
 2. The UAV of claim 1, comprising: amotivation system attached to the body to motivate the UAV along theconductor; and wherein the motivation system comprises a single set ofwheels coaxially aligned to engage the conductor.
 3. The UAV of claim 2,wherein: the single set of wheels are positioned above the body; and acenter of gravity of the UAV is located in a same plane as the singleset of wheels.
 4. The UAV of claim 2, wherein the motivation systemcomprises a first wheel and a second wheel coaxially aligned to engagethe conductor, wherein the UAV has a center of gravity positionedvertically below and in a same plane as the first wheel and the secondwheel; and the first wheel and the second wheel each comprising a motorelectrically coupled to the battery.
 5. The UAV of claim 2, wherein therotor system comprises rotor assemblies positioned below the motivationsystem.
 6. The UAV of claim 2, wherein the body carries a controller incommunication with the rotor system and the motivation system toautonomously maneuver the UAV.
 7. The UAV of claim 6, further comprisingnavigation sensors mounted with the body and in communication with thecontroller.
 8. The UAV of claim 2, wherein: the motivation systemcomprises a single set of wheels coaxially aligned to engage the aconductor and positioned above the body, each wheel of the single set ofwheels comprising a motor electrically coupled to the battery; a centerof gravity of the UAV is positioned below and in a same plane as thesingle set of wheels; and the inductive coil is positioned proximate tothe single set of wheels.
 9. The UAV of claim 8, wherein: the bodycarries a controller in communication with the rotor system and themotivation system to autonomously maneuver the UAV; and navigationsensors mounted with the body and in communication with the controller.10. The UAV of claim 1, wherein the monitoring tool comprises a camera.11. A method of inspecting an aerial power transmission line system, themethod comprising: flying an unmanned aerial vehicle (UAV) to aconductor of the aerial power transmission line system, the UAVcomprising a body having a rotor assembly, a set of wheels coaxiallyaligned, and a battery; positioning the set of wheels on the conductor;inspecting the conductor with a monitoring tool; and harvesting, using acoil that extends between a plurality of arms connected to the body,electricity from the aerial power transmission line system and chargingthe battery.
 12. The method of claim 11, comprising: moving the UAValong the conductor; and wherein the moving the UAV along the conductorcomprises driving the set of wheels.
 13. The method of claim 11,comprising: moving the UAV along the conductor; and wherein the movingthe UAV along the conductor comprises operating the rotor assembly whilethe set of wheels is positioned on the conductor.
 14. The method ofclaim 11, wherein the harvesting electricity comprises positioning acoil proximate to the conductor.
 15. The method of claim 11, comprising:moving the UAV along the conductor; wherein the moving the UAV along theconductor comprises moving the UAV along a portion of the conductor bydriving the set of wheels while not operating the rotor assembly; andmoving the UAV along another portion of the conductor, with the set ofwheels on the conductor, by operating the rotor assembly.
 16. The methodof claim 11, further comprising traveling past an obstruction on theconductor by operating the rotor assembly to lift the set of wheels offof the conductor on a first side of the obstruction and landing the setof wheels on the conductor on a second side of the obstruction.
 17. Themethod of claim 11, wherein the set of wheels are positioned above thebody and a center of gravity of the UAV is positioned in a same plane asthe set of wheels.
 18. The method of claim 17, further comprisingtraveling past an obstruction on the conductor by operating the rotorassembly to lift the set of wheels off of the conductor on a first sideof the obstruction and landing the set of wheels on the conductor on asecond side of the obstruction.
 19. The method of claim 17, comprising:moving the UAV along the conductor; and wherein the moving the UAV alongthe conductor comprises moving the UAV up an incline by operating therotor assembly and maintaining the set of wheels on the conductor. 20.The method of claim 17, wherein the harvesting electricity comprisespositioning a coil proximate to the conductor.